Read and build a cladogram
Grade 9 Science Worksheet

Circle the best answer.
Ari builds a cladogram from the trait table of five animals. Which description fits the traits?
- Lamprey and trout share a node, and frog, lizard and dog join them at a later node
- Trout, frog, lizard and dog branch apart at one node, with lamprey outside that group
- Lamprey branches first, then trout, then dog; frog and lizard share the last node
- Lamprey branches first, then trout, then frog; lizard and dog share the last node
Bo builds a cladogram of moss, fern and pine from the trait table. Which description fits?
Tips to place: moss, fern, pine. No tree is drawn. Table: Traits of three plants (model data), 3 rows. Columns: plant | vascular tissue | seeds. Row 1: moss | no | no. Row 2: fern | yes | no. Row 3: pine | yes | yes. Tips to place: moss, fern, pine. No tree is drawn. Table: Traits of three plants (model data), 3 rows. Columns: plant | vascular tissue | seeds. Row 1: moss | no | no. Row 2: fern | yes | no. Row 3: pine | yes | yes. Tips to place: moss, fern, pine. No tree is drawn. plant vascular tissue seeds moss no no fern yes no pine yes yes Traits of three plants (model data), 3 rows. Row 1 Row 2 Row 3 - Moss, fern and pine branch apart at one node, with no closer pair
- Moss branches first; fern and pine share a node
- Fern branches first; moss and pine share a node
- Pine branches first; moss and fern share a node, since they sit side by side
Read this first
Traits of five model bugs (model data)
Tips to place: J, K, L, M, N. No tree is drawn.
bug three-part antennae spotted back hooked legs J no no no K yes yes no L yes yes no M yes no yes N yes no yes Esme builds a cladogram of five model bugs from the trait table. Which description fits the traits?
- J branches first; L and M share a node, since they are neighbors in the table
- J branches first; K, L, M and N then branch apart together at one single node
- J branches first; K and L share a node, M and N share a node, and the two nodes join
- J branches first, then K, then L, and finally M and N share the last node
Traits of four plants (model data)
Cladogram (model data), rooted, not to scale. Tips from left to right: moss, fern, pine, flowering plant. Node W is the root, where moss and node X branch apart. Node X is where fern and node Y branch apart. Node Y is where pine and flowering plant branch apart.
plant vascular tissue seeds flowers moss no no no fern yes no no pine yes yes no flowering plant yes yes yes Kira marks seeds on the plant cladogram. Where did seeds first appear, using the fewest changes?
- The pine tip and the flowering plant tip, with one mark on each tip
- The branch to node Y, once, before pine and flowering plant split
- The branch to node X, before fern and the seed plants split
- The stem below node W, before moss branched off from the others
Traits of five animals (model data)
Cladogram (model data), rooted, not to scale. Tips from left to right: lamprey, trout, frog, lizard, dog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where frog and node Z branch apart. Node Z is where lizard and dog branch apart.
animal jaws four limbs keratin skin growths hair lamprey no no no no trout yes no no no frog yes yes no no lizard yes yes yes no dog yes yes yes yes Luz adds the hair mark to the cladogram. Hair is yes just for dog. Where does the mark go?
- On the dog branch, since it sets dog apart but groups no other animal
- On the lizard branch too, since lizard sits next to dog
- On the branch to node Z, shared by lizard and dog
- On the branch to node Y, shared by frog, lizard and dog
Use this
Cladogram (model data), rooted, not to scale. Tips from left to right: lamprey, trout, frog, lizard, dog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where frog and node Z branch apart. Node Z is where lizard and dog branch apart.
Noah reads the clade that starts at node Y. Which animals does it hold?
Cladogram (model data), rooted, not to scale. Tips from left to right: lamprey, trout, frog, lizard, dog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where frog and node Z branch apart. Node Z is where lizard and dog branch apart. Cladogram (model data), rooted, not to scale. Tips from left to right: lamprey, trout, frog, lizard, dog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where frog and node Z branch apart. Node Z is where lizard and dog branch apart. W root X Y Z lamprey trout frog lizard dog - Lizard and dog, the animals that descend from node Z
- Frog, lizard and dog, the animals that descend from node Y
- Trout, frog, lizard and dog, the animals that descend from node X
- Frog and dog, leaving out lizard because it sits between them
Traits of four plants (model data)
Cladogram (model data), rooted, not to scale. Tips from left to right: moss, fern, pine, flowering plant. Node W is the root, where moss and node X branch apart. Node X is where fern and node Y branch apart. Node Y is where pine and flowering plant branch apart. The mark for vascular tissue is on the branch to node X. The mark for seeds is on the branch to node Y.
plant vascular tissue seeds flowers moss no no no fern yes no no pine yes yes no flowering plant yes yes yes Pia reads the clade at node X: fern, pine and flowering plant. Which trait do its members share?
- Vascular tissue, which arose on the branch to node X
- Flowers, which the flowering plant has
- Vascular tissue, which arose on the branch to node Y
- Seeds, which pine and flowering plant have
Ren flips the branches at node Y, so frog is now drawn last. Which statement about the redrawn tree is true?
Tree A tips from left to right: lamprey, trout, frog, lizard, dog. Tree B (model data), rooted, not to scale, is Tree A with the two branches at node Y swapped. Tips from left to right: lamprey, trout, lizard, dog, frog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where node Z and frog branch apart. Node Z is where lizard and dog branch apart. Tree A tips from left to right: lamprey, trout, frog, lizard, dog. Tree B (model data), rooted, not to scale, is Tree A with the two branches at node Y swapped. Tips from left to right: lamprey, trout, lizard, dog, frog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where node Z and frog branch apart. Node Z is where lizard and dog branch apart. Tree A W X Y Z lamprey trout frog lizard dog Tree B (model data) rooted, not to scale W X Y Z lamprey trout lizard dog frog - Nothing changes about relationships; lizard and dog still share node Z
- Frog is now the closest relative of dog, because the two animals sit side by side
- The relationships changed, because flipping moves the branches to new ancestors
- Frog is now the most advanced animal, because it is drawn last
“rooted, not to scale” Tala swaps the branches at node W, so moss is drawn last. Which statement about the redrawn tree is true?
Tree A tips from left to right: moss, fern, pine, flowering plant. Tree B (model data), rooted, not to scale, is Tree A with the two branches at node W swapped. Tips from left to right: fern, pine, flowering plant, moss. Node W is the root, where node X and moss branch apart. Node X is where fern and node Y branch apart. Node Y is where pine and flowering plant branch apart. Tree A tips from left to right: moss, fern, pine, flowering plant. Tree B (model data), rooted, not to scale, is Tree A with the two branches at node W swapped. Tips from left to right: fern, pine, flowering plant, moss. Node W is the root, where node X and moss branch apart. Node X is where fern and node Y branch apart. Node Y is where pine and flowering plant branch apart. Tree A moss fern pine flowering plant W X Y Tree B (model data) fern pine flowering plant moss W X Y - Moss is now closest to the flowering plant, because the two sit side by side
- Moss is now a descendant of node X, because its branch moved
- Moss now branched off last, because it is drawn last
- Moss is still the outgroup, and the relationships are unchanged
Use this
Tree A tips from left to right: lamprey, trout, frog, lizard, dog. Tree B (model data), rooted, not to scale, is Tree A with the branches at every node swapped.
Zee compares Tree B, with tips dog, lizard, frog, trout and lamprey, to Tree A, with lamprey first. Does Tree B show different relationships?
Tree A tips from left to right: lamprey, trout, frog, lizard, dog. Tree B (model data), rooted, not to scale, is Tree A with the branches at every node swapped. Tips from left to right: dog, lizard, frog, trout, lamprey. Node W is the root, where node X and lamprey branch apart. Node X is where node Y and trout branch apart. Node Y is where node Z and frog branch apart. Node Z is where dog and lizard branch apart. Tree A tips from left to right: lamprey, trout, frog, lizard, dog. Tree B (model data), rooted, not to scale, is Tree A with the branches at every node swapped. Tips from left to right: dog, lizard, frog, trout, lamprey. Node W is the root, where node X and lamprey branch apart. Node X is where node Y and trout branch apart. Node Y is where node Z and frog branch apart. Node Z is where dog and lizard branch apart. Tree B (model data) W X Y Z dog lizard frog trout lamprey - Yes; Tree B has frog beside lizard, so frog is now a closer relative of lizard
- No; Tree B is Tree A flipped at every node, so the relationships are the same
- Yes; lamprey is now drawn last, so it is now the newest group
- Yes; dog is now far from lamprey, so the relationships changed